This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A007867 #11 Feb 03 2016 10:43:07 %S A007867 1,1,2,7,22,82,307 %N A007867 Complementary pairs of `homogenized' N-free graphs with n nodes. %C A007867 I believe this is an erroneous version of A241156. - _N. J. A. Sloane_, Apr 18 2014 %H A007867 Jacinta Covington, <a href="http://plms.oxfordjournals.org/content/s3-58/1/1.extract">A universal structure for N-free graphs</a>, Proc. London Math. Soc. (3) 58 (1989), no. 1, 1--16. MR0969544 (89m:03028). - _N. J. A. Sloane_, Apr 18 2014 %Y A007867 Cf. A241156. %K A007867 nonn %O A007867 1,3 %A A007867 _Peter J. Cameron_